


Breakdown

by GravityPinefalls



Category: Gravity Falls
Genre: F/M
Language: English
Status: Completed
Published: 2017-04-13
Updated: 2017-04-13
Packaged: 2018-10-18 13:59:32
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 3
Words: 17,970
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/10618392
Author URL: https://archiveofourown.org/users/GravityPinefalls/pseuds/GravityPinefalls
Summary: The wheels on the bus go round and round, usually.  At the end of another summer, Mabel and Dipper find themselves waylaid halfway between Gravity Falls and Piedmont.  Thankfully, as responsible teenage siblings without even the slightest undercurrent of weird sexual tension between them, their unsupervised isolation does not cause them to discover any sort of inappropriate urges and then act upon them.  Oh wait-





	1. Chapter 1

 

_Breakdown, go ahead and give it to me._  
_Breakdown, honey, take me through the night._  
_Breakdown, I’m standing here, can’t you see?_  
_Breakdown, It’s all right._  
_It’s all right._  
_It’s all right._  
_\- Tom Petty_

Dipper and Mabel had just finished their third summer together in Gravity Falls - including their fifteenth birthday - and having said goodbye to what had become their summer home, they had every expectation to be sleeping in their own beds that evening.

They’d just crossed into California when the coach bus began to rattle and make grinding noises; the driver took an off-ramp and got nearly to the stop sign when there was a loud crunch and something large and important-looking fell out the back.  Dipper stuck his head out the window to study the oily engine fragments on the asphalt.  No obvious evidence of gremlins, but they were rather sneaky.  They’d stopped for dinner only an hour ago, and it was getting dark.  The twenty other passengers took out their cellphones and began to thoroughly complain into them, and Dipper struggled to hear the bus driver’s conversation over the radio.

The chorus of disappointment when the driver stood and announced the bus had broken down, the company had no other bus available that night, but they’d get everyone into a motel and pick them up first thing in the morning, roused Mabel, who somehow had slept through the bus crapping engine parts out onto the road.

“W-wha, are we home?”

“No, I think we’re still outside Redding,” Dipper said.  “We might be stuck in a hotel tonight.”

Several of the passengers were near enough to their destinations that they managed to get taxis or rides from friends, but most of them ended up dragging their luggage out of the dead bus and tromping up the off-ramp to a motel just up the street.  The clerk there studied the stack of vouchers the driver handed him, but eventually nodded and began checking people in.  

Mabel made something of a pillow fort out of their luggage as Dipper waited in line, and splayed herself out on it while playing with her phone.  The clerk had apparently worked up a rhythm from the previous five check-ins, and when Dipper handed him back the filled-out room rental contract, he seemed annoyed.

“Driver’s license,” the clerk said.  “I asked everyone in line to have their driver’s license ready.”

“I don’t have one.”

The clerk sneered at him over his glasses.

“You’re eighteen, right?  Can’t give you a room if you’re underage.”

“Of course I’m eighteen,” Dipper said, surprising himself with how easy the lie came to him.  “I just don’t drive, is all.”

The clerk sighed.

“Fine, whatever.  Room 122.  Take a left and go straight on.  Checkout at eleven.”

Dipper pushed the motel door open and sighed.  The no-smoking sign on the door was apparently a suggestion, as the scent of stale cigarettes emanated from the brown carpet.  

“Eugh,” he said.

“Ooo,” Mabel said.  “It’s so _trashy_ !  I _love_ it!”

The twins dragged their luggage into the room and made a pile beside the bathroom door, and then took a survey of their impromptu accommodations.  One bed with an ugly red comforter, lightly speckled with cigarette burns.  A dusty TV on a stand.  A sliding window with an A/C unit below.  A small closet.  A bureau painted puke-yellow, with drawers stuck closed, and Dipper not particularly interested in forcing open.  Three framed paintings of beaches arranged on the walls.

The shower _shooshed_ behind him.  He turned to the bathroom, where Mabel was dutifully testing the faucets.

“Dipper!  Water pressure!”

“Mabel?”

She was already digging toiletries out of her suitcase.

“I’m _weak_ , Dipper,” she said.  “Months of taking showers in that dribble in the Mystery Shack have _weakened_ me.  But this place has a shower that could strip paint, and I’m using it even if it takes my skin off.”

And with that, a purple bag under her shoulder, she slammed the bathroom door.

He sat on the bed.  Soft mattress, not too bad.  The comforter was in bad shape but the sheets underneath looked clean and smelled recently washed.  He briefly considered pulling out his blacklight, but decided he’d rather not know what he might find.  Perhaps the other bed-

He blinked.   _The other bed._

It was a single room.  One bed.

“Mabel, there’s only one -”

“Can’t hear you!” came the sing-song response, making it clear she could totally hear him, and this was followed with the sound of splashing and the shower curtain being drawn.

He sighed.  Fine.  There were some extra sheets in a shelf in the closet.  He’d arrange a spot to sleep on the floor, so she’d have the bed.  No big deal.

He pulled out his cellphone and called their parents.  Dad offered to drive up and get them, which Dipper thought was crazy - that was an eight-hour round trip, and even if he left right at that moment, they’d get into Piedmont close to 4am.  Why bother, when everyone could get a night’s sleep, and the next bus would pick them up tomorrow morning and have them home by lunch?

After assuring their parents everything was fine, and further promising they would stay in the room until the bus arrived and not let anyone else into the room (why would they?) Dipper hung up and turned on the TV.  Only then did he realize how weird the situation was - _there were no adults here_ .  Nobody was in charge.  Sure, he and Mabel were on their own most of the time when in Gravity Falls, but they always came home to the Mystery Shack, always slept in their attic room, and always had _someone_ \- Stan or Ford or at very least Soos - somewhere in the house, watching over them.

Well, considering what they’d been through, being on their own for one night wasn’t _that_ weird, was it? He and Mabel had to be the most responsible fifteen-year-olds he knew.  Along with Stan, Ford, and many of their friends in Gravity Falls, they’d literally saved _reality itself_ two years earlier - that has to count for _something_ !  Throw in the fact that they had regular summer jobs as Assistant Manager in Charge of Design, Human Resources, and Marketing (Mabel) and Lead On-Site Cryptozoological Researcher (Dipper) of the World Famous Mystery Shack, and it was only fair the twins get _some_ credit for adult independence.  Plus, they’d be starting their sophomore year in high school in a couple weeks.  Next year, they’d be old enough to drive.  In two years, they’d be going to college.

Obviously, then, sharing a hotel room for a night and catching a bus the next morning was a Test of Adulthood barely worth noticing.  What were they going to do with this sudden freedom?  Run out to some sketchy street corner and buy booze and drugs?  Call in some hookers?  Get real.

Dipper had tossed aside the dirty comforter, kicked off his sneakers and stretched out on the over-starched-but-clean bedsheets, and was a few minutes into a rather bland True Crime docudrama, when the bathroom door popped open, billowing steam.

“Oh, man, that was _amazing_ ,” she said.  “I heard you call Mom and Dad?  Are they freaking out?  I bet they’re freaking out.”

“Yeah, they’re a little concerned, but as long as we don’t miss the bus in the morning I don’t think it’s gonna be a big deal.”

“Awesome.  Hey, I hope you don’t mind, but I used up all the towels.  They’re not very big.”

Why, oh why, did _that_ make him turn his head and look at her?  

Mabel grinned.  A white towel was wrapped around her head, holding up her mid-back-length reddish-brown hair, except for a few stray tufts slipping through behind her ears.  A second white towel covered her midsection, tight across her chest, forming a respectable bit of cleavage, and reaching down as far as her upper thighs.  

 _Oh wow she’s a girl oh wow Mabel is a girl oh wow_ , said Dipper’s brain.

“Yeah, no problem,” he said, playing it totally cool, yep, totally cool.  His voice definitely wasn’t doing weird things, and he definitely wasn’t struggling to make his eyes move normally, neither staring at Mabel nor obviously averting his eyes.

He stifled a sigh of relief as she turned around and began to rummage through her suitcase, and quickly fixed his gaze on the TV, doing his best to ignore anything in his peripheral vision.

 _It’s nothing, Dipper.  You’ve been on that damn bus for four hours, daydreaming about Wendy.  You just worked yourself up a little too much, that’s all.  And anyway, anything and everything gives you a boner these days, you know that.  It doesn’t_ mean _anything.  Just keep it together for ten minutes, for god’s sake.  As soon as she’s done with the bathroom, run in there, rub one out, and you’ll be right as rain.  Whatever you do, don’t read anything into this.  For God’s sake, Dipper, don’t read anything into this._

“Hey, Dipper, you packed my hair dryer, right?”

Mabel had run out of room in her suitcase, so he had packed some of her stuff into his own.

“Yeah, it’s in there.  Plus those three sweaters of yours.”

“Which bag?”

“The gray duffel,” he said, turning to his left and pointing it out.

_Stupid, stupid Dipper._

On the plus side, she was turned away from him as she unzipped one of his bags and began to dig through it, which meant she could not see his inappropriate and involuntary reaction.  On the minus side, he was having an inappropriate and involuntary reaction.  

_This stupid motel.  Why are the towels so small?  Mabel isn’t even that tall - I know in fact that she’s exactly five-foot-three - and she can barely even cover herself with one.  I mean, look at this.  The bottom of the towel doesn’t even get to mid-thigh on her.  Look at how the fabric just kinda follows the curve of her ass and drops down not even six inches before stopping.  Look, she can’t even bend over without the fabric sliding up so far you can almost …_

He wasn’t sure what he saw - probably just a shadow.  But he looked back to the TV, pulled his legs up to help conceal his erection, and thoroughly convinced himself he had _not_ just caught a glimpse of his first real-life vagina.

He remained stone-still as Mabel returned to the bathroom with the hairdryer and a change of clothes, and over the next five minutes managed to relax, and decided everything was fine.

To his relief, Mabel had put on somewhat conservative sleepwear - a baggy pink t-shirt with a gold star pattern, and loose purple pajama pants with yellow-and-black smiley faces.

They watched TV for another hour or so, and Dipper grabbed a t-shirt and gym shorts from his bag and went into the bathroom, brushed his teeth, and got ready for bed.  He felt reasonably under control, but boxers and gym shorts would make it quite challenging to conceal any further erections.  And so, out of an abundance of caution, he dropped his shorts and boxers and began to masturbate.  It would have to be quick, he knew.  He ran through his favorite fantasies.  Wendy.  Hell, throw Pacifica in there too, that’ll work.  It felt good, it got him hard, but the buildup to orgasm got only so far.  Too stressful, this way.  Mabel was on the other side of the door, watching TV.  Could she hear him?  How long could he be in here and not make it obvious he was doing what he was doing?  No good. He had to speed things up.  Mabel bending over in a towel.   _It doesn’t mean anything._  The towel sliding up further, further.   _It was just an accident, she didn’t mean it_ .  Mabel looking over her shoulder, a goofy grin, a knowing look, a sultry smile. Mabel pulling the towel off, still bent over, her ass on full display. Whispering something sexy and strange yet quintessentially Mabel, like “Cum at me, bro,” and then _oh crap here we go yep we’re cumming, oh wow that just snuck up on me, probably shoulda gotten a handful of tissues ready earlier than this, welp, sorry bathroom door._

A tap on the door.

“Dipper, are you okay?”

“F-fine!” he gasped.  “I’m fine!”  Sucking breath through his teeth.  An inch and a half of cheap wood laminate and foam core was all that separated Mabel from a defilement beyond imagination.  

“Uh … okay, I just thought you were sick.  You were making weird noises.”

“I’m good, just give me a minute, okay?”

His knees were weak, but he had no time to relax.  Running the sink, rinsing semen from his cock and hands, and then gratuitous application of tissues to the newly-decorated bathroom door.

He slowed his breathing, put on fresh clothes.

_All right, so that was twelve types of fucked up.  But it’s out of your system now, right?_

He unlatched the lock, turned the knob on the bathroom door.

_Welcome everyone, to America’s favorite game show: Pretending You Didn’t Just Jack Off to Your Sister._

“Did you throw up?” Mabel asked.  “You look all pale, and out of breath.”

 _No, but_ you _certainly would, if you had any idea what I was doing..._

“No, just … just got a little sick to my stomach for a minute.  I think I’m fine now,” he said.

Without skipping a beat, Mabel ran into the bathroom, filled a cup of water, and set it on the bedside table beside him.

“I had some juice from the last rest stop, but I drank it already,” she said.  “I could look around for a vending machine, maybe find you some ginger ale?”

_God, Mabel.  Just when I think I can’t sink any lower, you have to throw it in my face, and show me how little I deserve you._

“Mabel, you don’t have to do that.  I’m feeling much better, honestly.”

She reached for his face, brushing his hair away from his forehead, regarding the birthmark there a moment before placing the back of her hand there.

“Well, no fever.  And you look like your color’s coming back already.  Maybe it was just something you ate?  I _told you_ not to eat the sushi at that truck stop!”

“Mabel, you _dared me_ to eat the sushi at that truck stop.  And I only had one piece and spit it out anyway.”

“Dipper, you dummy, if I _dare_ you to do something, you _know_ that means you absolutely, _positively_ shouldn’t do it!  I’d never, ever dare you to something unless it was the _worst_ idea ever!  Don’t you know _anything_?”

He laughed.

“Right, right.  Fair enough.  Anyway, if I had food poisoning from _that_ , I’m pretty sure I’d be barfing my lungs out around now, so I’m probably fine.”

“Aw, man,” Mabel said.  “And here I thought we were gonna play doctor.”

_Wait, what?_

She sighed, stood up.

“Anyway, here, have a shot.  Bap!”

She punched him in the arm - rather hard! - and giggled as she rolled over him and took position on the other side of the bed.  

With an hour left on the TV movie, they made bets on who was the real killer.  Mabel made a celebratory cartwheel during the reveal - it was, in fact, the person who was most obviously the killer, in a sort of reverse-red-herring.  The second-most-obvious killer, which Dipper chose, was just some shady guy who had nothing to do with this particular crime.

“You just guessed,” Dipper said.  “You were lucky.”

“No I didn’t!  It was obvious right from the start, dummy.”

“How?”

“Because the actor playing him was Rex Rexington, you doof.  Not super-famous, B-list at best, but every other suspect was some no-name character actor.”

“I have no idea who that is,” said Dipper.

“Exactly.  You made a fool’s bargain, bro-bro.  You were all like duuuh-”  

Mabel pantomimed chewing a pen, drawing on an invisible chalkboard, all the while rolling her eyes.

“And all the time I’m over here like, psheew!”

Mabel pantomimed … Dipper wasn’t really sure.  Waving her arms in the air, then pointing double finger guns at the TV.  

“And you know what they say in Vegas,” Mabel said.  “ _Always_ bet on ‘pshew!’”

“All right, you got me.  Fair and square.  What do I owe you?”

“Hmm.  Eternal slavery would be good.  Do my homework every day for the rest of my life?  Oh, I know.  Breakfast in bed.”

“Like, tomorrow?”

She bounced up and down on the bed.

“Yep yep!  They do a continental breakfast here.  It’s probably awful.  But if you set your alarm a little early, you can go down there, make us up a plate with whatever looks good, and bring it to the room.  And we’ll just hang out here for a couple hours before we get dressed and pack up.”

“That actually sounds pretty fun,” he said.  “We should probably get to bed soon, though, if we’re gonna get up that early.”

“All right, lemme go brush my teeth.”

He was arranging the comforter and spare sheets on the floor when she caught him in the mirror, her mouth full of toothpaste.

“What’cha doing?”

“You get the bed; I’ll take the floor,” he said.

“What?  You can’t be serious.”

“It’s not a big deal,” Dipper said.

“Come on, you doof.  The carpet is filthy.  We’re sharing the bed.”

He picked up the pillows, shook them off, and returned them to the bed.  

He was under the sheets, reading a book about ghost-hunting he picked up recently, when Mabel was done with the bathroom.  She didn’t come to bed immediately, though, and her movements occasionally took his attention as she went through her before-bed stretching routine.  He averted his eyes when she did a handstand and her t-shirt slid down to expose her stomach.

“Ahh,” she said, sliding under the cool sheets beside him.  Laying on their backs, arms to their sides, they had about a foot of bed between them, which was hopefully enough.  She turned away from him, curling up a little, and spooning a pillow.

“Good night, Dipper,” she said.

“Good night, Mabel.”

 

 


	2. Chapter 2

Even with all the lights out, the room was not very dark - the floodlights of the hotel parking lot sent rays of light through the gaps in the curtains - and he could hear the occasional rumble of a truck downshifting on the nearby highway.

He lay still for well over an hour, but sleep wouldn’t come.  Maybe he slept too much on the bus?  He considered reading again; if he took the book into the bathroom then the light wouldn’t bother Mabel.  And it’s not like he needed a lot of sleep tonight anyway; he’d have plenty of time to nap on the bus tomorrow.  He stared at the digital clock on the bedside table, watching it switch from 11:04 to 11:05.

“Mmmpfh,” said Mabel.

She rolled over, and was now on her left side, facing him, squeezing the pillow tightly in her arms.

“Mabel,” he whispered, not wanting to wake her if she was still asleep.  “You still up?”

She said nothing, kept her eyes closed, but a slight smile on her lips formed and then faded.  He couldn’t help but smile back.

“Ah, what a shame,” he said.  “I guess I’ll just have to talk to myself then.”

He stretched out on the bed, hands behind his head.  He caught Mabel open one eye to see what he was doing, and then close it again.  He could see the tenseness in her face as she tried to stifle her smile, pretending to be asleep.  He knew this game, one of many they had together, the pastimes drawn from thousands of nights sleeping in the same room.  She was wide awake, but wanted to hear him talk to her.  She wanted him to say things he normally wouldn’t, things he was a little embarrassed about, things he wanted to say to her, but only if she promised to keep his secrets.

“Our second year of high school starts in two weeks,” he said.  “We have to start thinking about college soon.  We always talked about getting an apartment together when that happened, but I don’t know how likely it is we’ll even end up in the same town.”

He sighed.

“I can’t believe it’s only been two years since I made that ridiculous decision to stay in Gravity Falls and work for Ford.  And knowing what I set in motion, deciding to go out on my own without even talking to you about it … I honestly don’t know what to do, Mabel.  I always thought it would be you and me against the world.  And the  _ one time _ I forgot that - the one time I fooled myself into thinking we weren’t a team anymore -  I almost lost everything important to me.”

On some strangely protective impulse, he reached out, initially to gently pat her on the head, but as his fingers made contact, he instead stroked her cheek with the back of his hand.  She kept her eyes closed, but briefly bit her lips in response.

“I know you don’t like talking about it, and after two years, maybe there’s nothing left to say about Weirdmageddon.  But I still have nightmares, Mabel.  Not all the time.  Maybe once every couple months.  I wake up in a cold sweat, and feel exactly like I did when Weirdmageddon started - that you’d been taken from me, maybe even  _ killed _ .  And when I open my eyes, and see you asleep on the other side of the room, the relief just washes over me.  If I couldn’t do that - if I woke up from one of those nightmares, and you weren’t there, I don’t know what I’d do with myself.”

He jumped at Mabel’s sudden movement. A hand gripped the shoulder of his shirt.  Turquoise fingernails digging into the cotton fabric.

“Then I’ll  _ tell  _ you what to do with yourself, dummy,” she said.  Her eyes wide and shimmering, brimming with tears.  “You  _ call  _ me.  Even if it’s 3am, you call my cellphone right then and there, and we talk as long as you want to.”

He placed his hand on hers, squeezing.

“Mabel,” he said.  “T-thanks … if I feel like I need to … I’ll do just that.”

She nodded.  “You  _ better _ .  And if that’s not enough, send me a video chat, and I’ll get out of bed and show you I’m perfectly fine.”  She smiled.  “Buyer beware, though.  You’re getting bedhead Mabel, in a ratty t-shirt and granny panties.”

He chuckled.

“All right, I’ll be careful about that.”

Her hand relaxed on his shirt, and he took it in his own, interlacing his fingers with hers.

“I’m glad though,” he said.  “As bad as it was to have you taken away, and as screwed up as that damn lotus-eater machine was that Bill put you in, there were a million worse things he could have done to you.  At least you were safe there long enough for the rest of us to get to you.”

“It could’ve gone really bad, though,” Mabel said.  “If you weren’t able to convince me back then to rejoin the real world, everyone would’ve been trapped in there.  And with you doing everything you could to make me see the light … I don’t know what Bill’s creations would have done to you.  You might’ve been killed in there, and I would never know … or even  _ care  _ …”

He pulled her close, and she obligingly pressed her face to his chest, gripping his shoulders as he gently stroked her auburn hair.  He had the odd realization that she smelled nice.

“The whole thing was exactly what I asked for, you know,” she said.  “I didn’t know I was asking  _ Bill _ , but still … I can’t pretend he was some sneaky creature that deliberately twisted my wish into something bad.  It  _ was  _ my wish.  It was creepy and wrong because that’s exactly what I wanted, and I didn’t care.  God, I even made up a fake version of you, to make it easier to ignore you trying to help me.  I mean, what the hell?  ‘Dippy Fresh’?  A Dipper that dresses better and constantly kisses my ass?”

“Eugh,” he said.  “God, he was the worst.”

“And I almost fell for it, too,” she said.  “For a while there, I was gonna choose the Dipper who told me everything I wanted to hear, instead of the  _ real  _ Dipper, who cares about me enough to tell me what I  _ needed  _ to hear.  I only realized, long after, he wasn’t the  _ dream  _ version of you, he was the  _ nightmare  _ version of you.  Stupid and shallow and manipulative.  Someone who would smile and pat me on the back and encourage me as I destroyed myself, and took everything and everyone I cared about with me.”

“I know,” he said.  “It’s all right.  I’m just glad you’re not mad at me for breaking into your fantasy world, and seeing that part of you.  I can’t even imagine what that world would look like now, after a full year of high school drama.”

“No kidding.  You thought Dippy Fresh was bad  _ then _ …”

She caught her breath.  A blush formed across her cheeks.

“God, Mabel.  I’m afraid to ask.”

“Then  _ don’t! _ ”

The intensity of her demand shook him.

“S-sure, of course.  I’ll drop it.  Dropping it right now.  It’s dropped.”

She broke the embrace, turned away, buried her face in her pillow.

“It’s all your fault,” she said.  “You’re just too good to me. You saved my life so many times.  You sacrificed all kinds of things to make me happy.  I don’t think I’ll ever trust anyone as much as I trust you.”

“Mabel, I’m pretty sure you saved my life just as often.  And all that other stuff - I don’t have any regrets.  If I could do it all over again I wouldn’t change a thing.”

“Ugh, you just … you don’t understand.”

“Then make me understand,” he said.

She sighed.

“Well, it’s like ...  I like dating, I like boys, and I’m pretty sure I’m good girlfriend material.  But I always feel on-guard.  I never get that feeling of comfort and safety I have with you.  Maybe my standards are too high.  I mean, I can’t exactly demand every boyfriend save me from a monster at some point.  I know you and Wendy aren’t exactly  _ dating _ , but the way you interact, just really  _ getting _ each other - I’d  _ love _ something like that.”

“Well,” Dipper said, rubbing his head, “to be fair, Wendy did save me from, like, way,  _ way  _ more monsters than I ever saved you from.  Like, I seriously lost count.  She went full Road Warrior during Weirdmageddon, and I wouldn’t have had a shot in hell of saving you without her.  So maybe that’s the trick - you gotta find some guy to fight through hell with.  Boom, deep, heartfelt romance.”

He rubbed her shoulder reassuringly, feeling her back tense at the touch and then relax.

“I’m the worst,” she said.

“No you’re not,” he said.  “Come on, look at me.”

She turned, and he propped himself up on one elbow to face her, his left hand free to brush the hair from her face.

“You’re telling me I’m such a great brother, that I set the bar too high.  How am I supposed to take that badly?”

“You just … you don’t understand.  You’d  _ hate me _ if you did.”

“You know better than that, Mabel.  There’s nothing you could say - nothing you could  _ do  _ \- that could ever make me hate you.  Not ever.”

Perhaps she took that as a challenge.  

Her hands flew to his face, gripping his cheeks as she brought her lips to his.  A brief kiss, but forceful, just enough to get her point across.  The taste of cherry lipgloss, the slight scent of mint toothpaste.  Her lips so soft, so warm.  Mabel pulled back, her brown eyes full and round and wet, more vulnerable than he’d ever known her to be.  Something in his brain rotated and clicked into place.  A puzzle he had not yet solved.  That he didn’t even know existed.  And the solution here, right in front of his face.  What if there really  _ was  _ something going on here, something he would never believe unless it punched him right in the nose?  If he allowed himself to, could he admit to himself his sister was indescribably beautiful?  Would he dare admit to himself how desperately he wanted her?

She pulled back, tears streaming down her face.

“Oh, God,” she sobbed.  “Oh God, it’s worse than I thought.”

“Mabel,” he whispered.

“I’m sorry, I’m sorry.  I thought if I kissed you … if I kissed you like I’ve been wanting to … that would finally knock some sense into me.  I thought it would be all gross, and the urge would go away.  But it’s not going away, Dipper.  I’m so sorry.  You can have the bed.  I’ll sleep on the floor and I promise I won’t do anything like that again.  I swear.”

She rolled over to her side to get up, her movement spurring him into action.  He couldn’t explain it.  Instinct.  Love. Lust.  A need to dry her tears.  To soothe her pain.  A need to prove to her he meant what he said - that  _ she could not make him hate her _ .  No matter  _ what _ .

He grasped for her shoulders, pressed her back to the bed, and brought his mouth to hers, silencing a surprised “Dip-!” with his lips.  He could smell the salt of her tears on her skin, feel her breath interrupted by sniffles of her runny nose.  He knew he would not release her on his own; she would have to  _ make him _ let go.  Her hands moved up his arms, gripped his shoulders, fingers digging into flesh, and he was ready, he was prepared, for her to push him away.  What would happen then, he did not know.  An awkward night, for sure.  Years of therapy.  A completely destroyed relationship between them.  But at least Mabel would know  _ she  _ was not the bad one.  If there  _ must _ be this crime, then let them  _ both _ be criminals.

When Mabel pulled at his shoulders, drawing him down to her, he was shocked at the realization of just how much he wanted her to do exactly that.  Had he ever felt anything nearly as good as the sensation of Mabel sliding her hands over his back, up to his neck, and running fingers into the hair at the back of his head?  Had he ever lived a moment so perfect as that miniscule gesture of Mabel’s fingers tilting his head slightly to his right, as she turned her head to  _ her  _ right, aligning their lips so that they might kiss with open mouths?  Had he ever before known a pleasure that could compare to Mabel inviting him to slide his tongue into her mouth, the playful welcome of her own tongue on his teeth and lips?  

It was  _ extraordinary _ . This was a free-for-all.  This was a meal for starving people.  He slipped a leg over her, straddled her, supported his weight with his left hand, his right hand cradling Mabel’s head.  They could barely breathe, and low and desperate moans echoed in his head, at least half of them not his own.  But he couldn’t stop.  He needed air.  But he needed Mabel more.

Had Dipper thought to check the radio clock on the bedside table - and had time any meaning in this place - he would have noticed he and his sister had been sloppily making out for the better part of twenty minutes when he finally came up for air.

“Ho- holy shit,” he gasped.

“Y-yeah,” she said.  “Are we seriously-?”

“I guess we are,” he said.

Straddling Mabel’s waist, his hands on either side of her shoulders, her hair splayed so prettily over the white over-starched hotel pillows.  He loved her.  More than anything.  What was he without her, his other half?  How obvious was it now, that she was his soulmate?  That his only satisfaction in life was to be with her?  That the only thing he wanted to do in his life was spend it, all of it, with her?

Mabel reached to her right, clicking on the lamp, filling the room with light and shadow.  She reached for his face again, but did not pull him close and kiss him, merely held him still, studying his face, and he made no move to discourage her.

“God,” she said.  “It’s not fair you’re so handsome, Dipper.”

“You always say I look like a dork,” he said.

“Well, duh, I’m your sister after all.  But I almost never mean it anymore.”

He chortled at this, and she took advantage of the distraction to grab fistfuls of shirt on his upper back and pull, and he ducked his head slightly as she pulled the garment over his head and down his arms, and lifted one hand and then the other so she could disentangle it from his arms and toss it aside.

“Hmm,” she said.  “Even better.”

Clearly she was hallucinating; even the in rare moments of being comfortable with his body Dipper would not rate Shirtless Dipper as anything above “acceptable.”  He’d gotten tall and thin over the past couple years, and under very forgiving lighting conditions might be confused for “toned,” but he was not at all muscular.

“I thought you said something about having high standards,” he said.

He flinched as she placed her hands on his chest, tracing the lines of his pecs and abs.  Or, perhaps more accurately, the most likely locations of such things.

“Oh, stop that, Dipper,” she said.  “You’re hot.  Girls tell you that all the time, don’t they?”

“You’d be the first, Mabel.”

“Are you serious?  Not even Wendy told you that?”

“I’ve gotten ‘handsome’ from her a few times.  Never ‘hot’ though.  I mean, she’s from a family of lumberjacks, for god’s sake.  Have you  _ seen  _ how stacked her brothers are?  They have muscles that haven’t even been discovered yet.”

She giggled.  “Well, that’s fine for them, but I don’t want anyone like that.  I want you, Dipper.  Just like you are.”

He allowed another minute or so of her tactile exploration before speaking again.

“Uh, Mabel, is this a one-way thing, or do I get to … ah, touch you too?”

She blushed.

“Oh, y-yeah, of course, Dipper.  I thought - I thought you just didn’t want to …”

“I mean, would it be too weird, if I just went for your, ah -?”  

Failing to get the word out, all Dipper could do was pantomime squeezing something with one hand.

She laughed, and raised her hands above her head, inviting him to remove her shirt.

“All right, your turn,” she said.  “Not much to see, though.”

“I’ll be the judge of that,” Dipper smirked, grabbing her shirt and pulling it off.

Mabel’s pale blue sport bra did nothing to accentuate her curves - quite the opposite really; that was its purpose, after all - but Dipper was excited all the same.

“Geez, we’re really doing this, aren’t we, Dipper?”

“As long as you’re okay with it, Mabel.”

“You bet I am.  Topless Twins?” said Mabel.

“Topless Twins,” said Dipper.

His breath caught as she grabbed at the elastic band at the bottom of her sport bra and pulled it off.  Her breasts were small, as she said, but so perfect, so beautiful.  Soft, round, creamy flesh, each of them just barely large enough to cup in a hand, each perfectly accented with a dull red areola and firm nipple at at its peak.  

She gasped as he reached for her, giggling as he palmed her breasts and teased her nipples with his fingers.  He had to admit, after all this time, he really  _ was  _ curious about Mabel’s body, about how she’d developed into a woman in the seven years or so since they were eight-year-olds sharing a bath.  He was fine, perfectly fine, with ignoring such idle and dangerous curiosity.  But given the chance to see his sister all grown up - it was just so incredibly  _ exciting _ .

“Ah,” she said.  “Dipper.  That feels … really good …”

It soon became a game, to test Mabel’s skin, find all the spots she liked being touched the most.  Her breasts, of course, were the focus of his attention, but he knew it would please Mabel far more if he was more creative in his explorations.  He found the places she was most ticklish on her ribs and stomach, to her protest, but also, that she enjoyed it when he reached around her and stroked her back.  She closed her eyes, as if entranced, and her hips began to move in slow circles under him.  Dipper knew that such movement would be his undoing before long.

He  kissed her, giving her breasts only a moment’s reprieve before he moved from her mouth, kissed and nibbled at her neck, and advanced downward to her chest.  Dipper wasn’t sure what pleased him more - the lovely moan she made as he took her nipple into his mouth, or the taste and texture of her taut flesh.  He suckled Mabel with gusto as she gripped his hair and held him to her chest.

Her hips began to move again, slow circling undulations which called out for his attention.  He felt quite certain they would go no further - breasts were one thing; surely she would not allow him to do anything below the waist.  Nevertheless, he began to kiss his way down her chest, down to her fluttering stomach, all the while Mabel’s hands stroking his hair.  He paused at the waistband of her pajamas, waiting for permission to cross this critical line.

“Dipper,” she whispered.  “I don’t … I don’t know what to do …”

“Whatever you want,” he said.  “Anything and everything.  Or nothing.  Just ask, Mabel.”

“But if it’s weird … if you don’t like it …”

“Don’t worry, Mabel.  I promise you.  Whatever you want to do right now is  _ exactly _ the right thing to do.”

“You  _ know  _ me, Dipper. I can’t do serious stuff like this.  I’ll make it all silly.”

He glanced up, reached for her hand, squeezed reassuringly.

“I wouldn’t want you any other way, Mabel.”

“You sure?  What if I said something totally ridiculous like ‘Oh, Sir Dippingsauce,  _ please  _ don’t go; I haven’t had a  _ moment’s  _ rest since we crossed paths in that haberdashery and you set my soul  _ afire’ _ ?”

Dipper grinned.

“Well, I’d probably say something totally ridiculous like ‘My dear Lady Mableton, I am ever at your service; I beg you put me to whatever use best suits you,’” he said, adding an absurdly flourished hat-tip/salute/bow at the end.

She giggled,  _ squealed  _ really, hands over her mouth, and then extending one hand to him, which he took in his hand and kissed.

“The Lady Mableton has some very lovely breasts today,” he said.

“Why thank you, Sir Dippingsauce.  I grew them myself.”

“And is there anything I might help you with today, Lady Mableton?”

“Well, since you ask, and if it’s not too much trouble, I should appreciate it very much, Sir Dippingsauce, if you would remove my pajama pants.  Very, very slowly, if you please.”

“The slowest, Lady Mableton.  And, perchance, would the Lady prefer to retain her panties at this time?”

“For the moment, yes.”

“Excellent, My Lady.  You have indeed selected our finest choice of depantings.”

He couldn’t help smiling as he hooked fingers under the waistband of Mabel’s pajama pants and slowly drew them down, exposing light pink cotton panties dotted with purple hearts.

“The Gentleman will forgive the Lady for neglecting to wear her sexy panties this evening,” Mabel decreed.

“The Gentleman insists there is nothing for the Lady to forgive,” Dipper countered.

The pajama pants down to her knees now, the fabric catching here and there on a bit of stubble just barely visible on her calves.

“The Gentleman will  _ further  _ forgive the Lady for not shaving her legs this week,” Mabel added.

“The Gentleman again insists there is nothing to forgive.”

He drew it out for a minute, maybe two, the fanciest of depantings, before the fabric slipped off her ankles and he placed it aside.  Mabel was beaming, stretching her legs, splaying her turquoise-painted toenails at him.  He began to stroke her bare legs, enjoying the warmth of her skin, the tenseness of muscle and tendons beneath.

“And how did Lady Mableton find this performance?” he asked.

“Well,” she said, “the Lady certainly didn’t  _ dislike _ it, but she has a lot of depantsing candidates to meet today.  Many of them with  _ years  _ of experience in depantsing the  _ finest  _ royalty in Europe.  You may leave your resume with my secretary.  We’ll call if we find something for you.”

She grinned, side-eyeing him.  He’d moved aside to get her pants off, but was still sitting on his knees, making it easy for him to bow dramatically.

“My dear Lady Mableton, I throw myself at your mercy.  Please, give me a chance to prove myself!”

“Well, all right.  One more chance.”  Mabel pantomimed opening up a book and scanning its entries with a finger.  “Ah, it seems all my depantsing interviews are booked up today.”

“How tragic,” he said.

“Something just opened up, though.”

“Do tell,” he said.

“Have you any talent, Sir Dippingsauce, in the fine art of removing a girl’s panties?”

“By great coincidence, Lady Mableton, I was just now considering entering that particular industry.”

“Fantastic. I entreat you then, to remove my under-est of garments.”

His heart fluttered in his chest as he reached for the waistband of Mabel’s panties.  Was this really happening?”

“W-wait,” she gasped.

Her hands gripped his, and he froze, looking up to her.

“Dipper. Don’t - don’t freak out if it  … if it looks weird or anything.”

“Mabel.  God, Mabel, you don’t have to worry about that.  I promise.”

“I just - I don’t know what you’re expecting.  I mean, I haven’t even shaved my  _ legs _ for  _ four days _ now.  And the basement level at Club Mabel gets the occasional  _ trim  _ at best, so you’re lookin’ at some grade-A bush coming your way.  I would never - I mean, if it was anyone,  _ anyone _ else, I would never ever want to go full-frontal all disarrayed like this. And, holy crap, I can’t even  _ start  _ about the panties.  Like, the  _ worst _ .  The unsexiest panties ever, am I right?”

“Look at me, Mabel.  I don’t want you done up.  I don’t want your business all staged like an open house.  I want you as you are, every day of your life, natural and normal and perfect.”

Her cheeks burned red.

“All right … but even still … I’m all …”  She waved her hands in an incomprehensible gesture.  “Bleurgh.”

“Bleurgh?”

“You know.”

“I’m sure I don’t.”

They were still, for a moment.

“I’ll stop, if you want me to,” he said. “But …”

“But?”

“... I don’t want to.  I’m sorry, I’m awful.  But Mabel … Oh my God, Mabel, I never … I never,  _ ever _ wanted anything in the world more that this … right here, right now … I could die here, Mabel, lightning could strike me dead and I’d be fine with it, because this entire evening was so perfect I couldn’t imagine anything better.  And still …”

“Still?” she said.

“Still,” he breathed, “if you will let me … if by some chance you’d even  _ consider _ me good enough for it … God, Mabel, I want to see you,  _ all _ of you, every part of you, because I already know you’re so far from ‘Bleugh’ you’re not even in the same time zone.”

She shifted her hips, cheeks burning.

“It’s all … squishy,” she said.

“Perfect,” he said.

“And the inside bits … they kinda poke out of the outside bits, so it’s all all weird and wrinkly.

“Perfect,” he said.

“And I’m getting pretty wet,” she said.

“Perfect,” he said.

“And I have a dick,” she said.

“Perf- wait, what?”

He glanced up as she burst into laughter.

“S-sorry,” she said.  “You had a rhythm going on there.  I wanted to make sure you were really listening.”

He sighed.

“Really making me work for this, aren’t you, Mabel?”

“I’m worth it, aren’t I?”

“Yeah.  You are.  Of course you are.”

“All right, all right,” she said.  “Just gimme a sec.  Let me work up to it.”

She breathed in deep, held it in, let go of hands so she could make fists in front of her face and then shake her hands out.

“Hooo, alrighty,” she exhaled.  “Oh boy oh boy this is exciting.  I mean, you’re the first boy to ever look at it … I mean, since we were kids, anyway …”

“Y-yeah,” Dipper said.  “I’ve never actually seen one, in real life anyway.”

“Plenty on the Internet, though,” she said.  “You are  _ so bad _ at clearing your history.”

“Ah, yeah…”

“And it’s not gonna look like one of  _ those _ , so get that out of your head right now.”

“I know, I know.”

She took in a couple more deep breaths.

“All right,” she said.

“You’re sure?” he asked.

“Yep.  Panties time is over. Take ‘em off, if you please”

“Fast, or slow, or-”

“Like a band-aid,” she said.  “Heck, toss ‘em across the room.  Where we’re going, we don’t  _ need _ panties.”

He held his breath and quickly pulled Mabel’s underwear off, tossing them over his shoulder.

“All right,” she said, “In reflection, that was dumb.  There’s no way I’m wearing those again if after they’ve spent the night on this nasty carpet.  Can you go after them?  You tossed ‘em behind the TV.”

“Gotcha.”

He jumped off the bed, reached around the TV stand, shook them off.

“Five second rule, right?” he said.

“My hero,” she said.  “Come, take your reward.”

He turned back to her, and froze.  She had scooted back on the bed a little, and incredibly, had spread her legs and drawn up her knees a little, showing him everything.

“Your reward is  _ vagina _ ,” she said, her voice a husky stage-whisper.

“W-whoah,” he said.

He placed her underwear at the foot of the bed, with the rest of their clothes, and cautiously sat beside his naked, spread-eagled sister.

_ This is real.  This is really her.  This is Mabel, perfectly and deliciously naked, offering herself, everything she has.  And she’s offering it to me. She really believes I’m worth all this. _

“Oh, geez, you’re staring.  Is it really that bad?” she asked.

“N-no,  _ God _ no, Mabel.  You are so beautiful I can hardly stand it.  Can I … can I touch you?”

“Yeah, of course.  Just be gentle, okay?”

He traced along her thighs, along the short sparse curls of her mound - honestly, he didn’t understand what she was on about there - along her puffy outer labia, and the tiny bit of inner labia poking out from between them.  Mabel’s breathing quickened as he found the nub at the apex of her vulva, and quickly began to circle her clit.

“Dipper … maybe you can be a little  _ less _ gentle …”

“Mabel?”

“You’re kinda teasing me,” she said.  “I mean, it feels good.  It feels really, really good.  But there’s more to it than just the outside.”

“You - you mean I can … doesn’t that hurt, though?”

“I mean, don’t jam your fist in there, duh.  But now you got me so wet, I can easily take a finger, maybe two.  You wanna feel what it’s like inside?”

“Mabel,” he whispered, “oh, god, absolutely.”

He traced and index finger up and down her vulva, working through the petals of her labia, and soon his finger was coated with warm, clear, fragrant liquid.  He felt the heat of her intimate flesh, sticky-slippery and beautiful, but couldn’t quite figure out the geometry.  Was there an entrance somewhere, or was this as far as a vagina goes?

“Lower,” she said.  “It’s way down there, Dipper.  Here.”

She took his hand, guided him, and pushed Dipper’s index finger into something hot and wet and tight and indescribably perfect.

“Hauuugh,” she groaned.  “Oh yeah, that’s in there …. oh, wow, Dipper, that’s like a million times better than when  _ I _ do it…”

Her expression, her voice, her breath, all conspired to overwhelm his senses.  He cautiously moved his finger deeper, then drew out a bit, carefully feeling out the contours of the wet tunnel that gripped him so tightly.  Mabel moaned, and gripped his shoulder.

“Mabel, is this - am I doing it right?”

“And  _ how _ !” she laughed.  “God, Dipper, that feels so great.  I mean, man oh man, this is the absolute best.”

She gripped his wrist, keeping his hand between her legs, and with her right hand gabbed his hair and pulled his lips to hers.  They kissed deeply, and he continued to finger her, making her hips move and shake.

“Mmm, Dipper,” she whispered, breathing into his ear.  Her breathing was becoming fast and shallow.  “It’s no fair.  I’ve been playing with myself for  _ years _ , and somehow  _ you’re _ the expert at this?”

“Mabel, you mean it?  You really like this?”

“You kidding?  You’re like halfway to making me cum already.”

God, he  _ ached _ for her, every part of him.

“You really mean that?  I mean, if I keep going…”

“Y-yeah,” she said.  “Ah, I’m so selfish, I’m not even doing anything for you…”

“Mabel, you are doing  _ plenty _ for me, I assure you.”

“So you don’t mind?  It’s all right for me to cum?”

“I am seriously going to lose it in my pants if you keep saying stuff like that,” said Dipper.  

Without his prior self-help session, he probably would have.

“So what, is that a yes or a no?” she said.  “Hmm?”

He pressed his forehead to hers.

“Yes.  Definitely. Absolutely.”

She giggled.  “All right,” she said.  “On one condition.”

“Name it.”

She kissed him dragging her fingernails through his hair.

“I’m gonna need two fingers in there, and I wouldn’t mind it if you gave my clit a little attention.”

“I think I can swing that,” he said.

He adjusted his position, sliding his middle and ring fingers into her, and quickened his pace, Mabel’s core now hot and slippery and making delightful little squishy noises as he fingered her.  After building up a rhythm, he sought out the nub he had seen before by touch, and after carefully gauging Mabel’s reactions, proceeded to press firmly on her clit with the pad of his thumb, rubbing left and right as he continued to plunge his fingers deep into her.

_ Augh, it’s like trying to rub my stomach and pat my head at the same time, _ Dipper thought.   _ Looks like that might be the trick to it, though. _

He watched Mabel’s her face as she closed her eyes and embraced him tightly.

“Haah,” she groaned.  “Oh geez.  Oh, Dipper, it’s coming.  Keep going!  Just like that, don’t change anything!  Ah, there, right there!  Ah!  Ah! Haaah!”

Her body convulsed, her hips shaking, her core rapidly tightening and relaxing around his fingers.  God, she was so beautiful.  He held her close, held her tight, and when he felt sure her orgasm has passed, and moved to extract his hand from between her legs, she grabbed his wrist, splayed fingers over his hand, and kept his hand in place, firm against her quivering core.

“Dipper,” she whispered.  “I’m sorry, just … a little longer…”

He kissed her cheek.

“Take all the time you need, Mabel.  I’m not going anywhere.”

He lay on his side, one hand propping up his head, the other captured in the warmth between Mabel’s thighs.  They stayed there in silence for a few minutes; Dipper thought she may have fallen asleep, in which case, he was quite happy to stay still the rest of the night.  Never had he seen anything as beautiful as the naked girl laying before him, and never had he felt anything as pleasant as the warmth of her womanhood against his palm.

She sighed heavily, and released the death-grip on his hand, and began to laugh.

“Mabel?”

“Sorry,” she said.  “Oh geez, I’m the worst.  But I couldn’t help thinking it.”

“Thinking what?”

“Remember the secret room we found in the Mystery Shack?  With that carpet?”

“Yes, Mabel, I  _ do  _ in fact remember the magical carpet that temporarily caused us to  _ exchange bodies _ .  Because it was  _ horrifying _ .  I really wish I’ve forgotten.”

She giggled.

“I was just thinking - you know, because of that - that this is technically the  _ second _ time you’ve been inside your own sister.  Ya big perv.”

“Oh, for god’s sake,” he said.

Mabel dissolved into giggles, crossing her arms over her stomach, and he moved atop her, and proceeded to stifle her giggles with kisses, to only partial effect.  His entire body felt warm.  It was just so perfect, so right, to kiss Mabel while she was laughing.

“Mmm,” she said, again taking his head in her hands.  “You’re poking me with your dipstick,” she said.

“Ah, sorry.”

“Don’t be.  I like it.”

He gasped as she reached down and gripped his shaft through his clothes.

“Oh, wow,” she said.  “You really are hot to trot, aren’t ya?”

“It’s your own fault,” he said.

She began to stroke him through his shorts and underwear.  He was ready, more than ready, to cum.  But he held off.  He had no idea when they might be able to do this again, if ever.  He needed more from her.  Needed to see more, do more.  

“So, Dip-dip, what’s next on the menu?”

“Well, I was thinking I really want to kiss you for a while longer.”

“We could certainly do  _ that _ ,” she said.  “But I was thinking more along the lines of attending to  _ your _ needs.”

“All right.  I was thinking I really  _ need _ to kiss you for a while longer.”

“You know what I meant,” she said.

“I know, and I want that too, but give me a minute to work up to it.”

She nodded, and he kissed her once more, before trailing kisses down her neck.  Her skin was warm and salty-sweet, and he kissed and licked his way to her breasts, detouring there for a good long while as he kissed and suckled the creamy skin and delicate nipples, leading her to intensify her grip on his hair.

His mouth got as far as her waist before Mabel realized his intentions.

“Whoah there cowboy,” she said.  “You’re wandering into dangerous territory.”

“Oh?” he said.  “What’s so dangerous about it?”

“Come on, Dip, you wouldn’t seriously, like, put your  _ mouth  _ there, would you?”

“Why not?”

“Ah, geez,  _ because _ .”

“You think I’d be bad at it?”

“What? No, of course not.  I just … Dipper, you don’t have to that.”

“But what if I want to, Mabel?  What if I really, really want to?”

He pressed his lips to the hollow of her hip, and looked upward, not quite sure of his expression - sexy, he hoped, but perhaps more pleading, even begging.

“Oh boy, you’re really serious, aren’t you?” she asked.

“Mmm-hmm.”

“Ah, god.  I am  _ never _ gonna be able to look at you the same way, Dipper.”

“Probably not.”

“Ah, man, I cannot  _ even _ ,” she said, and sighing, put pressure against his head, guiding him downward.

Holy god, the scent of her.  The taste.  Dipper placed a single kiss on her clit, and he was gone.  It was better than he imagined. Better than he could  _ ever  _ have imagined.  The flavor of his twin sister, salty and musky.  His tongue delved into her recesses, sampling her vaginal juices, and those too were delicious.  He sucked hard on her clit, and Mabel’s legs suddenly wrapped around his head, squeezing his ears with her thighs, partly - but not quite - muffling out her voice.

“Oh god oh god oh god what the hell Dipper what are you oh god you are killing me I am dying dipper oh god oh god oh hell…”

Her hips began to move against him, quick rabbit-like thrusts, and he gripped her firm ass with his hands, holding her close, nibbling and slurping at her intimate flesh, his own body singing with the joy of Mabel’s obvious pleasure.   _ I’m doing this.  I’m really doing this to her.  Making her feel so good she can barely speak.  I’m so happy.  I can’t believe how happy I am. _

“Haaah,” she said, starting to sit up, failing, falling backward on the pillows, her hands releasing him, falling to her sides, gripping the sheets tightly, arching her back, raising her hips.

He took her clit into his mouth and sucked hard, rolled the firm nub between his tongue and teeth, bringing her the edge.  He slowed his pace for a moment, barely a few seconds, letting her catch her breath, and then sped up again, pushing her right off that edge, making her crash down, making her  _ feel it _ .

“Dipper, oh god, oh god Dipper, I love you, I love you so much, oh god, oh my god…”

She trembled against him, and he slowed his pace again, looking up through the fuzzy screen of her pubic hair, studying the expression on her face, the unbridled ecstasy, the tears in her eyes.  She was still shaking, still riding the last waves of her orgasm, when she reached for him, grasping his hair, pulling painfully, making him crawl up her body.

“Kiss me,” she hissed.  “Oh god, Dipper, I need you to  _ kiss me _ .”

Had she given him a minute to plan things out, he probably would have run to the bathroom, washed Mabel’s juices from his face, maybe even washed out his mouth so she needn’t have to taste her own fluids.  He was glad, though, not to do the latter - the salty tang of Mabel’s vagina was something he wanted to keep on his tongue as long as he could.  He considered, for an instant, refusing to kiss her so he could take care of such things.  But her urgency was too great to be countered, and she brought his lips to hers, and wrapped her legs around him, and she kissed him without restraint, greedily plunging her tongue into his mouth to the extent it was impossible for Mabel not to taste her own fluids.  If she did, though, she didn’t seem to mind in the least.

He could do this all night, he felt certain, but they broke the kiss after a minute or two, and stared at each other.

“ _ You _ are a man of many talents,” she said.  “Where the heck did you learn  _ that _ ?”

“I … I don’t know, Mabel.  I just - did whatever seemed right.”

“Well, Dip, you have  _ remarkable _ instincts.  You’re sure there aren’t any sex tips in those journals you’re not telling me about?  Or maybe you’re just  _ so good _ at solving puzzles you could figure it out in nothing flat.  Like an expert safe-cracker, except with  _ vaginas _ .”

“Ah … maybe it’s something like that,” he said.

“Ooo, is there porn about that?  You’d know if there was, wouldn’t you?  Oh man, that’s an awesome idea.”  She raised her hands, gesturing out the wide spread of a marquee sign.  “The Vagina Whisperer.  Oh man, this stuff writes itself!”

He laughed.  God, he loved this.  Her reliable spontaneity.  Her perfect weirdness.

“And speaking of ideas …” she said.

“Mabel?”

“I have a few.  Move over, Dip.  I’m taking the wheel.”

Her ankles were still locked behind his back, so when she threw her hips she easily rolled them over, pinning his back to the mattress.  She released her legs and straddled him, looking down at him, her brown doe-eyes burning with intent, her hair in remarkable disarray of half-dislodged barrettes and bobby-pins, her arms thin but toned, her breasts delicate and round, her hips firm against his thighs.

“Holy god, you’re beautiful,” he whispered.

More kisses.   _ Oh, god, my god, let me remember this, let me memorize every kiss forever, oh god her taste, oh god her warmth, every touch of her tongue and lips a prayer. _

“Hey, Dipper?”

“Yeah?”

Another kiss from her, and then:

“I’m sorry about interrupting you earlier.  I didn’t realize what you were doing until after I knocked on the door.”

“Oh … ah, so you knew … wait, then why the whole thing about asking me if I was sick?”

“I figured it was a good cover story, so you wouldn't get too embarrassed.”

“And the ‘playing doctor’ line?”

“Just a little tease,” she giggled.

“So you’re not weirded out by that?”

“Of course not!  I do it too!” she said.  “I mean, sometimes you just gotta take care of things, right?”

“Right,” he said.

“And anyway, you don’t have to worry about me catching you doing that stuff.”

“I don’t?”

“Of course you don’t,” she said.

She placed her hand on his chest, her index finger tracing circles and spirals and figure-eights around his pecs and nipples.

“I mean, if I go into your bedroom, and I forget to knock - or maybe, you left the door open - and I find you sitting on your bed, and stroking yourself …”

Her hand moved downward, circles and ellipses on his abdomen.

“I’d just give you a thumbs up and close the door for you,” she said.  “No judgment. No teasing.  Because it’s nothing to be ashamed of.”

“Oh,” he said.

“I mean, that’s how I probably would’ve handled it anyway, before tonight.  So the only thing that’s changed, really, is that when I close that door …”

Fingers moving downward, slipping under the waistband of his boxers.

“ … I might not be …”

The contact of her fingers on his shaft, making him groan.

“... on the other side of it.”

Her hand encircling him, his body responding, back arched, hips raised.  He moaned, and she kissed him, stroking him slowly, fingers around the shaft, her thumb gently brushing the head.  Being touched by her … stroked by her … it was beyond imagination.  Never had he felt anything so pleasant, so reassuring, so arousing.

“Mabel,” he whispered

“Oh, wow,” she said.  “You’ve got a serious situation going on down here.  You don’t mind if I take a look, do you?”

“You don’t … you don’t really want to see it, do you?”

She laughed.

“Of course I do, silly.  You can’t spend all this time poking me with it and expect me not to be curious.”

He blushed.  Her eyes widened.

“Dipper, geez, after all the stuff you’ve done for me, why would you think I wouldn’t … I mean … I’d  _ never  _ let you do that stuff if I wasn’t ready to do the same for you.  And you … you  _ want  _ me to do this, don’t you?  It’s okay if you don’t, I just …”

“Bleaugh,” he said.

“Bleargh?”

He waved in the general vicinity of his penis, which was - for the record - still being gripped by Mabel.

“Oh,” she says.  “You think you’re …”

“Yeah.”

“So like,  _ exactly  _ how I felt just a couple minutes ago?”

“Probably.”

“Well … I’m touching it right now and it seems pretty good to me.  I mean … it’s warm, and hard.  Nice length, good thickness … yeah, if I was shopping at the penis store I’d probably buy one of these models.  I mean, I’d haggle for it, obvs.  Floor model and all.  And I know for a fact it’s been on way,  _ way  _ too many test drives.”

He chuckled.

“All right, all right.  Sorry, I just - ah, god, I must sound so whiny.”

“S’all good, Dip-dip.  I know how you feel.  We good?”

“Yeah, we’re good.  Thanks.”

“Awsome.  So let’s see what’cha packing.”

He couldn’t help but blush as she yanked down his shorts and underwear and put them aside, and knelt beside him, carefully studying his nudity.

“Mmm,” she said.  “Not bad, not bad.”

She took him in her hands, cupping his balls, stroking his shaft, and he descended into inarticulate grunts and gasps.

She giggled.

“Oh man,” she said.  “Oh, I’m gonna have fun with this.”

Dipper was quite sure he was having an out-of-body experience.  Mabel, gloriously naked before him,  touching him this way.  The warm, delicate fingers surveying his genitals. And all the while, she was smiling.  She was happy.  She enjoyed this.  It was too much for him to process.  Too much for him to believe.

She stroked him a moment more, and then leaned forward, kissing him.

“You totally destroyed me back there, you know.  I mean, I never,  _ ever  _ thought a boy would do that to me.  And I  _ absolutely  _ never thought I’d actually  _ like  _ it.  I mean, do you have any idea how good it feels, to have someone you love so much put their mouth on your privates, and just lick and suck you until you lose your freaking mind?”

She scooted down the bed, straddling his legs, on her hands and knees, the closeness of her face to his penis shocking him out of his stupor.

“M-mabel - you wouldn’t - you don’t have to-”

She laughed.  “Yep,  _ that’s  _ the look I was waiting for.  Oh yeah, Dip.  This is  _ totally  _ happening.  Oh man, I wish I could take a picture of your face right now.”  

She closed her eyes, leaned down, and - nuzzled him?  Murmuring softly, brushing her cheek against his cock.

“Mmm,” she said.  “You kinda smell nice down here.  But I bet you  _ taste  _ even better.”

He suspects he passed out for a moment or two at the sensation and the sight and the sound of Mabel Pines, his goofy twin sister, taking his cock into her mouth.

“Oh god oh god oh holy god,” said Dipper.

“Hauumn,” said Mabel.

“Mabel, oh god Mabel don’t - you don’t have to - oh god…”

She bobbed her head up and down, eyebrows furrowed in thought, apparently gauging his response as she experimented with suction, tempo, and the use of her tongue.  He could do little but fall back on the sheets, alternating from staring incoherently at the ceiling and staring incoherently at the gorgeous girl vigorously blowing him.

Oh, thank god he’d wacked off earlier - there’s no chance he’d last even a  _ minute  _ otherwise.

And if the actual sensation of her mouth and tongue weren’t enough, the sight of her would surely do him in.  The way she smiled with her eyes when her mouth was full ( _ of my dick oh god she’s my sister how is this happening _ ), the grin any time she withdrew, the hums and moans and occasional slurp.  Almost as if she enjoyed this every bit as much as he enjoyed doing the same to her.

“Mmm,” she said.  “I was right.  You  _ do _ taste good.”

It was mesmerizing, watching her head bob up and down on his shaft, occasionally withdrawing completely to lap at him with her tongue.  As if in a daze, he released his death-grip on the sheets, reached for her, gripped her hair.

She paused, looking up at him.

“Dip?”

He froze.

“Ah - s-sorry, I don’t mean to force you-”

Mabel smiled, grabbing both of his hands , placing them on either side of her head.

“I gotchu Bro-bro,” she said.  “Don’t like, jam it down my throat or nothin’, but if you wanna drive, you totally can.  Your hips keep moving, like I’m not getting the pace you want, or maybe you just need to move a little to make it feel right?  How about I just suck on it, and you move in and out?  You think that might work?”

“M-mabel…”

He took her offer, pushing her down with featherlight pressure, and she took him into her mouth with a playful “Haum!” and proceeded to suck.   _ Hard _ .  He groaned, and began to move his hips, sliding his cock in and out of her tight lips, building himself closer and closer to release as he gently fucked Mabel’s mouth.

After barely a minute of this, he withdrew, gasping, barely able to comprehend the sight of Mabel staring at him, mouth open, tongue just barely extended, and an inch away, his own erection, glistening with her saliva.

“Pfwah!” said Mabel.  “Oh man, that is  _ hot _ . I mean, just  _ sucking it _ is already riling me up, but making you hold me down, and show me  _ exactly _ how you want it … oh, wow, Dip.”

Absent anything else to do, she took him in his hands, stroking his length firmly, quickly.

“So, how’m I doing?  Getting close?”

“Ah … yeah, in fact … you might want to get some tissues or something …”

“Whaa?  After all the stuff  _ you  _ just did?  No way, Dipper.  You’re getting the full-service treatment.”

“F-full service?”

“Yep yep.  Wash and wax, tire cleaner, heck, I’ll even throw in an air freshener.  Gonna skip the underbody protection though - don’t think we’re ready for that one.”

She glanced at him, rolled his eyes at his expression, which was most likely one of total incomprehension.

“Geez.  You’re supposed to be the one who’s good at deciphering codes.  I’m saying I’ll keep the change.”

_ Still not comprehending. _

“I’ll take my milkshake to go,” she said.

_ Was she saying … no, no way. _

“Please, sir, I would like to purchase your entire stock of tadpoles.”

“Are … are blowjobs usually this confusing?”

“Augh,” she said, rolling her eyes.  “Dipper, you dummy.  I’m saying you can cum in my mouth.”

“Y-you can’t be serious!”

“As a heart attack!” she said.  “C’mon, I bet it’ll feel great.”

“Mabel,” he said.  “You really … you’re really okay with this?”

“Oh, you betcha.  I mean, I could switch up and give you a real nice handjob, if that’s what you want.  I don’t think I’m gonna have any trouble making you cum that way.  But if I keep going, like this …”

She kissed his shaft, and began to stroke him at an accelerating pace.

“I mean, yeah, the nicest thing I’ve ever heard about a boy’s sperm is it’s ‘not  _ that  _ gross.’  But that’s not your fault.  And right now, your whole body is gearing up to make some for me, and I know it’s gonna feel really really good when you do.”

She took him into his mouth, a quick suck and release, making him gasp.

“And I bet your orgasm will be even better if you know I’m enjoying this so much … that I love you so much … I’ll gladly take it, as much as I can.”

“M-mabel, oh, god, I’m really gonna lose it…”

“Mmm.  All right, broseph.  Show me what ya got for me.”

She took him in her mouth, stroking his shaft vigorously as she flicked at the tip of his cock with her tongue, eyes fixed on him.

_ Oh, off we go then.  Yep, that’s happening. Oh dear oh hell. _

His entire body went off on its own, trembling and shaking.  He didn’t understand.  He’d jacked off often enough to get a decent handle on what it felt like to ejaculate.  And it felt pretty darn good.  And it was  _ nothing _ like this.  This was Mabel.  This was Mabel doing this to him.  Her mouth was so warm.  So accepting.  Of  _ everything _ .  He thought he might cry.  Maybe he  _ was _ crying.  She deserved better than this.  This was beneath her.  And, oh god, she was looking at him.  He was cumming and she was looking right at him.  Sucking him.  Taking him.  All of him.  It defied understanding.  Why would she do this?  Why didn’t she understand he wasn’t worth this?”

He fell back on the bed, hips shaking, then slowing.  Then, and only then, did Mabel cease her efforts, slow her sucking, and even so, kept his penis in her mouth.  Only when his breathing slowed to a rhythm more compatible with life did she pull back, let his semi-hard penis slip from her mouth, and speak to him.

“Hwow,” she said.  “Thatsh halot moar dan hai hexpected.”

“Mabel,” he gasped.  “I’m sorry, oh God I’m so sorry, let me get some tissues-”

“Hwanna see ha mahjic shrick?”

She held up a hand.  Stared him down.  

Audibly swallowed.

“Mabel…”

She smiled.  Crawled up to him, staring him in the face.  Opened her mouth, stuck out her tongue.

“Ta-dah!” she said.  “Look, Dipper, I made a whole mouthful of your sperm totally disappear.  Amazing, right!”

“Mabel, you didn’t have to…”

“Oh, I  _ totally  _ had to.  You were looking at me all like-”  

She paused.  Made a face.

“Eugh, that … that stuff really sticks in your throat, doesn’t it?  Bleuch.  Hang on a sec.”

She ran to the bathroom.  

_ Oh god, please don’t throw up.  Please don’t let it be so bad I made her puke. _

She came back a minute later, kissed him on the cheek.

“So, now I know to do that  _ before _ brushing my teeth,” she said.  

“Mabel, I’m so sorry, I really am.”

“Oh, shush.  I knew what I was doing.  And I’d totally do it again.  Did it rock your world?  Because, from where I was sitting, I think I kinda rocked your world.”

“Yeah,” he said.  “Yeah, you certainly did.”

“Awesome,” she said.

She glanced at the clock.

“Oh, holy crap, it’s late.  We’re gonna be dragging our butts tomorrow.”

She flicked off the light, crawled over him, pulled up the sheets.

“No big deal, though.  After all, the day is saved, all thanks to the Oral Sex Twins,” she announced.

“We’re not … that’s not a thing.  We’re not calling ourselves that.”

She squeezed against him, closed her eyes, and patted his head gently.

“There, there, Captain Cunnilingus.  Your secret identity is safe with me.”

 


	3. Chapter 3

He never felt anything quite as peaceful as this, Mabel curled around him, cheek on his chest, arms around him, one leg hooked over his.  The contact of naked skin.  He slept, longer and more peacefully than before, but with trepidation.

There was precious little time left, and he couldn’t bear spending so much of it asleep.  

He had set the alarm for 8am, which would give them an hour to get dressed, repack their things, check out, and meet in the lobby for the replacement coach bus.  But something woke him around 6am - maybe a slight stirring of Mabel - and he couldn’t bear to close his eyes again.  She murmured softly in her sleep, and he gently traced his fingers up and down her shoulder.  So little time.  He wouldn’t waste a moment.  And for forty-five minutes he lay there, wide awake, holding her, studying the lines of her sleeping face, softly caressing every bit of skin he could touch.

Nature called.  He carefully extricated himself from Mabel’s embrace, scooting off the bed, and without waking, Mabel immediately grasped for his pillow and spooned it.  He chuckled softly and went to the bathroom, relieving himself and them splashing water on his face.

There was no way he was getting back to sleep.  And Mabel … the right thing to do would probably be to let her sleep as late as possible.  But of course they’d been doing quite the opposite of the right thing to do for some time now.

He left the bathroom, dug through his luggage, and pulled out a new change of clothes.  Once dressed, and with the room key-card in hand, he went over to the side of the bed and kissed Mabel on the temple.

“All right, Mabes.  I’ll see about getting us some breakfast.  Back in a bit.”

“Mmm,” she said, apparently half-asleep.  “Bring waffles.”

“I’ll do my best,” he chuckled.

The sun was just rising over the trees, and he shaded his face with his ball cap as he left the room and walked toward the hotel lobby.  Just before going in, though, he glanced across the street, to the gas-station mini-mart that was apparently just opening.

_Well, that’s convenient. I wonder if I should get us some soda or snacks or something before we leave._

He entered the store, grabbing a couple soft drinks and those fake-cheese-flavored chips Mabel likes, and paused.

_I wonder if I should …_

_No, no, absolutely not. There is no way, no way in hell Mabel would ever …_

_But … if she was interested in trying that ...  I mean, they aren’t expensive …_

_Shit shit shit._

Exhaling sharply, getting his wits together.

_You’re fifteen.  It’s not weird at all to buy them.  It’s responsible.  And if you don’t need them, it’s no big deal._

He casually walked over to the pharmaceutical aisle, pretending to be interested in the pain relievers and athletic bandages while checking out the boxes of condoms just a foot to his left.  

_Damn it, where do I even start?  So many types and styles and … sizes.  Oh, god, what if they … what if they don’t even make one small enough for … ah, god, this is the worst.  Ah, dammit, get it together Dipper.  Focus.  All right, nothing fancy, none of the flavored stuff or textures - I’ll figure out all that stuff some other day.  Lubricated is … good, probably?  And let’s … let’s be realistic, let’s get the smallest size, and if it doesn’t fit, well, that’s a nice ego-boost, isn’t it?  Ah, god, why don’t they have like a starter pack for this stuff?  I’m going to be in a lot of trouble if they don’t come with instructions..._

_All right.  That one.  That should do.  We’re doing this._

Dipper grabbed a 3-pack of Trojans off the shelf and made his way to the cash register.

_All right, let’s get our story straight.  You’re a college student.  No, no, nobody will believe that.  You’re a high school senior.  Yeah, good.  I’m traveling in my car, which I am able to drive, to visit my girlfriend.  Her name is Sandy.  She is a camp counselor at … ah, god, need a name, gotta think of a name …_

The cashier was a platinum blonde woman in her 30s, who had not been at all subtle in her application of baby blue glittery eyeshadow.  She chatted a bit with the elderly man in line before him, apparently here for his daily cup of coffee and danish, before sending him off.

Dipper placed his items - two soft drinks, a bag of chips, and a pack of condoms - on the shelf, and readied himself for the ensuing interrogation.

“That’ll be eleven fifteen, hun,” she said.

“Ah … yes, of course, that is a _completely normal_ price,” he said.

_Oh god just run you fool._

He shook it off, pulled out his wallet, gave her a ten and a five.

“One and two and three,” she said, slapping singles into his open palm, “and eighty-five cents,” she added, placing three quarters and a nickel atop them.

“T-thanks,” he said.  “There is nothing weird about this.”

_Oh god I was only thinking that why did I say that oh crap oh god._

She laughed, slapping the counter with a loud bang.

“Oh, sweetie-pie,” she said.  “I bet your girl is the happiest person in the County.  Oh, Lord, I remember being your age, and I would’a  married my prom date if he was half as brave as you.”

“I … can can leave though, right?” he said, stock still, eyes flicking left and right.   _This is probably where I get arrested.  At least I’m wearing clean underwear.  I have that going for me._

“Oh, shoot, I’m making it worse, aren’t I?  Yes, of course you can go.  But-”

She glanced around, her eyes catching a chilled display of small flower bouquets near the doors.

“-but make sure to take a complimentary bouquet,” she said.  

“Uh…”

“Trust me, kid.  I know a catch when I see one.  Good luck on your date!”

“S-sure, yeah, thanks,” he said.  

He took the plastic bag she had just filled, went to the cooler full of flowers, opened it, and took out a bouquet of pink carnations, wrapped in clear cellophane and held with an elastic band.  He looked back to the cashier, who gave him a thumb’s up.

He was about to thank her.  Or apologize to her, as he was not bringing this to his girlfriend.  Or confess to her, as he had committed unspeakable crimes and with all his heart intended to commit more.  But a gruff middle-aged man with a long beard and flannel jacket came into the store right that moment, and the cashier immediately engaged him in conversation.

Dipper left the store, stuck the flowers in the bag, moved the condoms to his pocket, and crossed the street back to the motel.

As the motel was, well first off, a _motel_ , but secondly, the dictionary definition of “seedy,” Dipper expected the “complimentary continental breakfast” to consist of a basket of store-bought breakfast pastries at most.  But he was pleasantly surprised.  The lobby where he and Mabel and the majority of other bus passengers had checked-in last night was apparently separated from a larger studio-type room with partitions he hadn’t noticed, and as it was now open, there was a rather impressive buffet, apparently catered in from a restaurant somewhere in town.

He scanned through the offerings.  Bacon and sausage were of course off the menu - Waddles and all - but there were individually-sized boxes of cereal, warming trays of scrambled eggs and hash browns,  a chilled bowl of fruit salad, several varieties of sliced bread and a toaster, packets of butter and jam, and also, of course, the holy grail.

_Yes, Virginia, There Is a Waffle Maker._

An actual waffle maker, with an actual container of batter.  And _pristine_ \- it was early enough he might be the first person to use it this morning.

No time to waste.  Dipper popped open the waffle maker, ladled a serving of batter onto it, and followed the instructions to close it up and turn it.  Two minutes later, the timer dinged, and he rotated the waffle maker back up and opened it.  Perfection.  He stabbed the delicious waffleness with a fork and dragged it onto a plate, and subsequently christened it with a scoop of butter and a criss-cross of maple syrup.  He also filled up a bowl with fresh fruit - cantaloupe and watermelon and grapes and strawberries - and a large glass of orange juice.  He stuck a handful of napkins and two each of forks and knives into the pockets of his cargo shorts, carefully balanced the waffle plate on the fruit bowl on the orange juice glass, and made his way back to the room.

He swiped the keycard, got the green light and whirr of gears, pushed down the handle and opened the door.  He was surprised to see the opaque curtains open, though the translucent ones were still in place - allowing light into the room but still allowing privacy - and the lights and TV were on.

Mabel was lounging on the bed, over the sheets, wearing a pink sleeveless shirt and pink-and-black-striped skirt.

She was wearing make-up.  Her pink lipstick was the most obvious, but perhaps the blush on her cheeks was also make-up blush.  He checked the clock.  It was just before seven.  He’d been gone barely ten minutes.  She just woke up and looked like she was ready for a date.

“About time,” she said.  “What’s the haul?”

He glanced around the room.

“Close your eyes a sec, Mabes.  I’ve got a surprise.”

“All right,” she said, and placed her hands over her eyes.

The bureau had an ugly brown tray on which the ice container and two plastic tumblers had been arrayed when they checked in.  He set those aside and arranged Mabel’s breakfast.  The waffle, front and center.  Fruit bowl to the left.  Orange juice to the top left.  And most importantly, the flowers.  The tumblers were tall enough to serve as a vases.  He ran to the bathroom, filled both with water, positioned one as a water glass, and the other as a vase.  He snapped the stems of the flowers six inches from the buds, and placed them in the vase-tumbler.  

With the arrangement complete, he stepped back, and immediately realised Mabel would have made something a thousand times prettier in half the time.

He sighed.

“All right, here you go, Mabes.  Breakfast in bed, as agreed.”

He saw it in her eyes, the excitement at his attempt, the recognition it was terribly disappointing, and the understanding it was literally the best he could do.

“Holy crap, you did it!  They really had waffles!”

“Yeah, the buffet was actually pretty good.  I guess they spent all the carpet-vacuuming money on a waffle maker.”

“And the flowers are a nice touch.  You really know how to make a girl feel special sometimes.”

He shrugged her off with a blush.

“Oh, and I got some snacks from the mini-mart across the street, so we have something for the ride.”

“Awesome,” she said.

He placed the tray on the bed, and they proceeded to eat together.  

“So, what time are we getting out of here?” she asked.

“Nine o’clock.  So, a little less than two hours.  Sorry about waking you up so early.”

“Oh, no problem.  I’m too excited to sleep anyway.”

“You look really good, by the way.”

“Aw, thanks!” she said, smacking him on the shoulder.

“So … are we … we just had weird dreams last night?  Is that how we’re playing this?”

She put down her fork.  “I … I don’t know.  I mean, obviously, once we get home, we gotta play it crazy cool.  But stuff like last night … it could be a one-time thing, of course, but I kinda don’t want it to be.”

“Y-yeah, same here,” he said.  “I mean, as long as we’re cautious … still … I just don’t know where this is going to go.”

“Yeah,” she said.  “It might just be a weird phase we’re going through, and we’ll look back on this crazy thing we did and make a pact to pretend it never happened.  But if it’s not … well, we’re gonna be living in our own place in a couple years anyway, right?”

“So we’re gonna … keep this on a slow simmer, then?”

“If we agree on it, yeah.  I mean, right off the bat, we gotta promise each other, if one of us hits the stop button, we just drop it and go back to what we were.  No hard feelings.  No jealousy when we start dating other people.  No weird ex-boyfriend/ex-girlfriend stuff.  And all the stuff we did in secret … well, we tell ourselves it’s just sleepover games that went too far once or twice.  Because if we can’t agree to that, and this all comes apart … then we better stop this right now before it gets too heavy.”

“Mabel,” he said.  “You’re right.  You’re totally right.  Let’s agree to that, right here and now.”

“So you’re in?” she said.  “Super-Secret Sometimes Naked Sleepover Twins?”

“One hundred percent,” he said.

They fist-bumped on it.

“All right,” she said.  “Well, now that we got that out of the way, and considering we still have the room for a while, I wonder what we should do with ourselves?”

“Ah … I don’t know … what do you suggest?”

_Please suggest “making out” ..._

“Well, you could help me on my scrapbook - I don’t have pictures from the last couple weeks developed yet, but everything up to that is printed and ready to go.”

He smiled.

“Sure, Mabel.”

“We don’t have to, though.  We have those travel games we got for our birthday, maybe play one of those?”

“That’d be fine too,” he said.

“Or maybe solve a mystery together?”

“A mystery?”

“Yep!  I call it: ‘The mystery of why Mabel jumped out of bed as soon as you left, and got herself as date-ready as she can in fifteen minutes.’”

“That’s … that’s an interesting mystery,” he said.

“I mean, seriously, was I too subtle?  I’m wearing lipstick at 7am, Dipper.  When have I _ever_ done that before?”

“So like, you wanna make out?”

She rolled her eyes.

“ _Duh_ , yeah, I wanna make out.  What’s a girl gotta do, send you a written invitation?”

“All right, I’m oblivious, I get it.  Here, let me get the tray out of the way.”

He moved the tray of mostly-eaten breakfast onto the bureau, catching the movement as Mabel drew something from under her pillow.

“I came prepared,” she said.  “Here.”

A folded piece of pink construction paper from Mabel’s scrapbook kit, with a heart in the center, ringed with pink glitter and stickers of rainbows and stars.  He opened it and read the inscription inside, in rather impressive calligraphy.

_Dearest Dippingsauce, would you do me the honor of making out with me?  Yours, Lady Mableton._

“You … you _literally_ sent me a written invitation to make out,” he said.

She laughed.

“Not my finest work.  I only had like two minutes,” she said.  “Not enough time to come up with even _one_ good pun.”

“Didn’t you just get those calligraphy pens a couple days ago?  How did you get so good at writing like this?”

“Aw, you noticed!  I wanted to try calligraphy for the scrapbook, so I spent a few hours practicing.  I mean, it’s still pretty janky, but good enough.”

“I mean, we still have to burn this,” he said.  “This is like, Exhibit A here.”

“To ashes,” she said.

He placed the card on the bedside table, leaned over, and kissed her, his heart leaping in his chest as she wrapped her arms around him.

“I can’t believe I never noticed before, how beautiful you are,” he said.

“Hee,” she said.  “You’re not so bad yourself.”

Hands over clothes, feeling her warmth against his chest, beneath his hands.  And the desperate need for more.

Soon his hands were under her shirt, cupping her breasts through her bra, and a few minutes later they’d each removed their shirts, and he had reached around her back, tugging at the bra clasp somewhere between her shoulders.  Mabel giggled.

“Man, the movies were _right_ .  These things _are_ really hard to get off,” he sighed.

“Geez,” she said.  “And I picked this one specifically to make it easier on you,” she said.

“You’re telling me you have bras that are harder to get off?”

“Yeah.  Because they have the clasp on the back.  This one opens at the front.”

“Oh,” he said.  “So I …”

“You’re literally as far away from it as you can be,” she chuckled.

“Right, so let’s try this again…”

He leaned back, finding the hook between the cups of her bra, and popped it open.  The excitement washed over him again as he parted the material and lay his hands on her bare breasts.

Soon, his mouth was upon her, suckling Mabel’s delicious nipples, nipping at her perfect breasts.  Soon, his hand was on her knee, moving up her thigh.  She pressed her face to the top of his head, gasping and moaning as he worked her breasts and rubbed her clit through her panties.  Soon, he hooked his finger under the thin layer of cotton, pulled her panties aside, exposed Mabel’s vulva to her touch.

“Oh god,” she whispered.

He dipped fingers into her, making her writhe her hips and moan, and soon her hand was busy as well, unbuttoning his shorts, slipping into his underwear, wrapping fingers around his shaft and stroking firmly.  He brought his mouth to hers, and for several beautiful minutes, they kissed deeply and pleasured each other, responding to each other, moans of satisfaction as he became hard in her fist, moans of satisfaction as she became wet beneath his fingers.

“Mmm,” she said.  “Dipper?”

“Yeah?”

“Maybe … maybe you don’t want to, and it’s okay if you don’t, but … did you want to, like, _do it_?”

He leaned back in surprise.

“‘Do it’?  You mean like … you and me … all the way?”

“Yeah.  I mean … we’re not gonna have another shot at this for a while, I think.  And maybe it’s not a good idea - actually, I _know_ it’s not a good idea - but still … all this kinda feels … unfinished, I guess?

“Mabel, you understand … that’s a _really_ serious thing … I mean, everything so far was pretty damn serious, but _that_ … Mabel, you’re still a virgin, right?  That’s something … that’s something I don’t think I could take from you.”

“Well, I’m as technical a virgin as a girl can be, no thanks to you,” she laughed.  “And, well, _you’re_ no better off.  Plus … well, it’s mine, to give, isn’t it?  My first time is something I can offer to anyone I want.  And if somehow I wanted that time to be _your_ first time as well … I dunno, I just …”

She sucked in a breath.

“I’m just saying, if you asked me to …”

He leaned close, kissed her cheek, her eyebrow, her forehead.  Soft kisses on every part of her face.

“Mabel,” he breathed.  “You’re my twin sister.  You’re my best friend.  And I love you.  I’ve never loved anyone more than you, and I think I never will.  And that’s the only thing that’s holding me back.  I don’t want to love you this way if it means losing all that.  But if I _can_ love you this way, and _still_ love you as a sister, and as a friend … if we can be lovers and friends and siblings, all at the same time …”

“We can,” she whispered.  “I know we can.  If we want to.”

“Then maybe,” he said, “this is just another adventure for us to share.  Just for us.”

“So you mean…”

He embraced her, crushed her against him.  He would never let her go.  Lips to her mouth, kissing her, tasting her.  Nothing sweeter than Mabel’s lips.

“Mabel,” he said.  “I know I don’t deserve it, I know we shouldn’t, but I’ll ask anyway.  Be with me.  Let me love you.”

She nodded, tears streaming down her eyes.

“The mini-mart across the street,” she said.  “When you were in there, did you see - do you think they might sell condoms?”

“Mabel, I already …”

He sighed, pulled the box out of his pocket, brought it to her face so she could see.

“Dipper.  Oh my god, Dipper.  You  mean - before I even said anything … you’re not just saying you want to because I brought it up.  You actually … you wanted this too!”

“I wasn’t … I wanted to be ready, just in case.  I wanted to ask you, but … I was so sure you wouldn’t want to … even if you said yes, I’d worry it was just to make me happy, and not because you wanted to do it just as much…”

“Dipper,” she whispered.  “Stupid Dipper, making me cry so much.  God, we’ve been here almost an hour eating breakfast, and making out, when we could’ve been … we could’ve been…”

She immediately yanked her skirt and underwear down, throwing them at the pile of luggage near the door, and then grabbed his shoulders, and drew him close, kissing and digging fingernails into his back before pressing his forehead to hers.

“I’m ready,” she said.  “I am _so_ freaking ready.  Let’s do this.”

“R-right,” he said.  He kicked off his shorts and underwear and reached for the box beside him, tearing open the side and pulling out one of the three foil-wrapped squares.

“Sorry,” he said, “give me a minute to read the instructions.  I want to make sure I get this right.”

“No hurry,” she said.  “Oh, wait, that sounded sarcastic.”  

She placed a hand on his thigh.  

“I mean it, Dipper, don’t hurry.  If we made a mistake, and I got pregnant …”  She shook her head.  “But that won’t happen.  Because you’re careful.  And I know I can trust you.  So take as much time as you need.”

He nodded.

_Right.  Expiration date checks out.  Package squishes like a pillow, so the air pocket is still there and it’s still sealed.  Tear open the side with fingers only.  Good so far.  Okay, which direction does it go?  Okay, it’s rolled up, it goes this way so … yeah, that’s it.  All righty.  Place it on the tip.  Squeeze the end to get the air out.  Roll it down to the base.  Hey, wow, that was pretty easy.  And I’ve got a layer of green plastic on my erect penis.  Sex is weirder than I ever imagined._

“All right,” he said.  “We’re all set.”

She rolled onto her back and spread her legs, hands reaching out for him.

“Awesome,” she said.  “We’re go for docking, Dipper-two.”

“Dipper-two?”

“Dipper-one ran out of fuel and never made rendezvous,” she said.  “The crew died horribly, sorry to say.”

“Mabel, where the hell did you-”

“You’ve been playing that spaceship game on your phone almost the way from Gravity Falls,” she said.  “I pay attention to your nerd stuff sometimes. And anyway, it’s kind of a good metaphor for sex, don’t you think?”

“Um…”

She waved her hands.

“Think about it.  Two spaceships out in the void, carefully approaching the other.  Trying to get to the exact same spot at the exact same speed at the exact same time.  So much stuff could go wrong, and it would be a disaster!  Kablooey!”

She splayed her arms out to suggest an explosion.  

“But,” she said, “if they talk to each other, plan things out - they can meet in a place that’s just perfect for them, and make contact, and become one.”

She reached out, held his arm.

“That’s _us_ ,” she said.  “We know almost everything about each other.  We can practically read each other’s minds sometimes.  So of course we’re perfectly compatible, in everything.  Even this.   _Especially_ this.”

“Mabel,” he whispered.  “How are you … how can you say something so perfect to me?”

“Did I say it right?” she said.  “I dunno, I’m kinda translating this all into nerd-speak on the fly, so I hope I got it right.”

“I think I got the message,” he said.

“Good,” she said.  “I was really afraid you’d make me talk more space to you, and that was pretty much the end of my crib sheet.”  She grinned.  “No more fancy words, okay?”

“Okay.”

“Awesome.  Now, if you please, stick your whatzit in my hoo-hah.”

He laughed, kissing her cheek.  

“My dearest Lady Mableton,” he said.  “With your permission, I shall now enter your girly-garden,”

“You are permitted,” she said.  “Indeed, Sir Dippingsauce, you are the guest of honor.”

God, this felt weird.  The experiences of last evening helped things along, as he pressed himself against her, knowing Mabel’s entrance was low, no, still lower, way way down there, and _oh there it goes_.  He braced himself on the bed with his knees and hands, the tip of his cock just barely inside her.  She gripped his shoulders and gasped.

_God I don’t want to hurt her don’t let me hurt her._

“Mabel,” he said. “Are you-?”

“Good!” she gasped.  “It’s fine!  Don’t cheap out on me.  I know you got more than that.  Slow, though!”

“Mabel, I swear to God I will stop right now if it hurts even a little-”

Her face that of burning fury and determination.  Her hands moved lower, grabbing his hips, digging her nails into his skin.

“Don’t you _dare_ ,” she said.  “Don’t you _dare_ stop.  I can take it.”

“Mabel …”

“It doesn’t hurt, I promise.  Keep going.  I wanna know … I wanna know what it feels like … when you’re completely inside me …”

He pushed, and within a few seconds was inside her entirely, and he adjusted position on the bed.  

“Mabel, is this - is this okay?”

  


“Mmm. Augh, it’s so weird,” she said.  “It’s like … I don’t know, like a new form in yoga class I’m just learning.  Finding muscles I didn’t know I had.”

“We can stop,” he said.  “We can always stop.  There’s no point at all if you’re not enjoying it.”

“Oh, don’t worry, it’s just a little uncomfortable.  Mmm, wow.  So you’re all the way in, huh?”

“That’s … that’s all I got, yeah.  Sorry...”

“Oh god, Dipper, I didn’t mean it like that.”  She pulled him close, kissed him.  “I mean, I can _definitely_ feel you in there.  And you are _really_ in there.  I just mean … it’s hard to believe.  You and me.  I took you _inside_ me.   _All_ of you.  And something about that … makes me so incredibly happy.”

“Mabel…”

“How does it feel for you, Dipper?”

“Warm,” he said.  “And tight.  It feels so good, Mabel.”

“Mmm.  I’m glad.  Ah, I think … yeah, I’m a little more relaxed.  You wanna start to move?”

“God yes,” he said.

She grinned, wrapped her arms around him.

“C’mere,” she said.

Balanced on his shins, her legs around his back, he slowly began to slide out and then in again, careful not to go to fast or pull all the way out, and gradually figuring out the movements of his legs and hips to make that happen.

She possessed him, gripping him with everything she had, vagina holding his cock inside her, legs holding his stomach against hers, arms holding his chest against hers, hands holding his mouth against hers.

He never thought he’d last this long his first time.  Ejaculating - _twice_! - the night before surely helped, and perhaps the condom helped as well.  Or perhaps all the sensations of making love to Mabel just overwhelmed him to the point he couldn’t focus on a feeling or thought long enough to be stoked to completion.

He was glad, as it was taking Mabel some time to build up, but he could see it now, her short breaths, beautiful little moans and gasps.  Seeing evidence of her building toward an orgasm quickly brought him closer to his own, and he carefully paced himself.

“M-mabel,” he gasped.  “I’m not gonna last much longer.”

“It’s all right,” she said.  “Whenever you want; I don’t mind!”

He felt it, the tension winding up like a watch spring, the need to release.

“What about you, Mabel?”

“Ah … getting there … it’s all right if I don’t, though …”

“Mabel…”

He adjusted his position, freeing a hand, moving his face away from her mouth and toward her chest, moving his free hand toward the juncture of her thighs.

_Hope this works._

“Uagh!” she cried, as he simultaneously sucked her nipple and thumbed her clit.

Her breathing quickened, and all the little muscles of her hips started to twitch as he worked her clit and nipple, all the while thrusting into her.

“Oh god,” she whispered.  “Oh god, oh god, I’m gonna … no, not like this - Dipper!”

She gripped his hair, dislodged her from her breast, and pulled his face to hers, almost nose-to-nose.

“L-like this!” she gasped.  “Oh god, I wanna cum like this!  Look at me Dipper!  Oh, god, it feels so good … ah … together … if we can do it together …”

“M-mabel,” he groaned.  He felt it, the coiled-up spring, the heat of impending release.  And at the same time, Mabel’s vagina tensing and relaxing around him at a rapid pace.

She squinted, tears spilling from the corners of her eyes, her mouth open wide, gasping for breath, and he felt sure he too had the same expression, a face of pure pleasure and desperate need.

“Dipper please,” she gasped.  “Oh please oh please I - hah!  Haaaah!”

He groaned, emptying himself inside her, the sensation of orgasm magnified a thousandfold by the sensation of Mabel’s own orgasm pumping his shaft.

They kissed, quick kisses, gasping, catching their breath.  She felt so _good_.  So right.  Ah, god, he wished he could stay inside her.

With a soft grunt, he began to pull away.

“Don’t pull out.  Not yet.”

“Mabel, I have to.  The condom.”

“Oh.  Right.”

He drew out of her, stunned by the beauty of Mabel’s post-coital vagina - glistening wet, flushed red, her entrance visibly spread open in the sudden absence of his penis.  He quickly grabbed some tissues, removed the condom, ran the bathroom sink and cleaned himself off before rejoining Mabel on the bed.

“Oh wow,” she said.  “Wowie wowie wow.”

“You all right, Mabes?”

“Better than all right,” she said.  “I mean … I had no idea it was like _that_ .  Oh man, we are _definitely_ doing _that_ again!”

“And we’re still … you know …”

“Oh you bet,” she said.  “Still Mystery Twins.  Just with like, a very _very_ secret handshake.”

She side-eyed him, getting a laugh out of him.

“All right, so we have like…”

He glanced at the clock.

“Shit.”

“Not enough time for two showers, huh?” she said.  “If we share, what are the odds we’ll actually get clean and not just fondle each other for twenty minutes?”

“Not great,” Dipper admitted.

“Well, I’ll take ‘em anyway,” she said.

He followed her into the bathroom, and to their credit, they kept the groping down to a minimum.  Half an hour later, they were dressed and packed and checked-out and waiting in the lobby.

When the bus turned into the parking lot, the twins exchanged a glance of disappointment.  This place was limbo, after all, a location between spaces and not a location unto itself.  In Piedmont, they were their parents’ children.  In Gravity Falls, they were lifelong friends of the town’s residents.  But in transit, they were neither.  They were simply Dipper and Mabel Pines, two people who loved each other more than anything else in this world.  Here, they were free to explore what that really meant.  To cast aside society’s taboos, act without judgment, speak the words unspoken.  Here, they were allowed to study their relationship in every aspect, find the curves and edges of each other's souls, and discover they were two puzzle pieces made to be joined in a way they would never have considered anywhere else.  Here they learned they could be one, if they wanted to.

As they found their seats, Mabel smiled at him, not a beaming smile, but lopsided, resigned.  He patted her shoulder and stretched out in the seat.  They could not speak what they were thinking here, which was fine, as he knew for sure they were thinking the same thing.  They had invoked a spell that might fade in the few hours it would take to get home.  A spell that perhaps only worked when he and Mabel were a hundred miles from anyplace and anyone they ever knew.  Would the previous twelve hours disappear from their memories when they reached their destination? If not, would they convince themselves it was all a dream?   _Should_ they?

The bus rumbled and jerked as the driver brought it onto the on-ramp, and Mabel bounced against him, almost knocking his book out of his hands.  He thought nothing of it as she placed her hand on his knee to steady herself, except for the way she let go.  It was done in an instant - surely too fast for anyone to notice, particularly amid the grumbled complaints of half-dislodged and understandably short-fused passengers.  But he felt her let go of his knee, letting her fingers slide up the inside of his upper thigh, just under the hem of his shorts, dragging her fingernails just hard enough to leave white marks on his skin, covered by the fabric as she let go, gripped the seat ahead of her and wiggled her butt back into her window seat.

They dared not make eye contact.  He knew for sure it would be days, perhaps weeks, perhaps months, before they would even speak of this again.  But her gesture - and the relief he felt from it - reassured him that what they started here would not end here.  It was small, just a coal, just a carefully packaged ember they would bring home with them, place in a safe spot, and feed just enough fuel to maintain its dull-red heat.  But someday, they would build a spot for it, carefully arrange kindling, place their ember upon it, and make it a raging fire.

Someday, he knew, whatever the consequence, he and Mabel would burn together.

  


_There is no sense in pretending_   
_Your eyes give you away_   
_Something inside of you_   
_Is feeling like I do_   
_And we’ve said all there is to say_   
_\- Tom Petty_

  
END

**Author's Note:**

> I solemnly swear I would never have even considered writing anything under the pinecest tag if not for me coming across a handful of DoublePines art pieces and suddenly finding a fire lit under me. So many feels! Weird feels! Honestly, it might be more correct to say this is fanfic of DoublePines's art rather than Gravity Falls itself. His/her character interpretations and interactions are just so perfect, and there's no way I would have gotten through this fic without flipping through my collection of his/her art, studying the detail of clothing and hairstyle and facial expression and body language, and trying to find words and phrases that invoke in me the same feelings.
> 
> I do hope you enjoyed!


End file.
